Centrifugal hydro-extractor



March 30, 1943. A. BAILLY 2,315,036

CENTRIFUGAL HYDRO-EXTRACTOR I Filed Feb. 8, 1940 Patented Mar. El), 1943 YES PATNT GEN-(IE Armand Bailly, Brussels, Belgium; vested in the Alien Property Custodian Application February 8, 15140, Serial No. 317,942; In Belgium February 8, 1939 8 Claims.

My invention relatesto improvements in the centrifugal hydro-extractor disclosed in the main patent application Serial No. 184,304, and comprising essentially a, conical filtering basket and a drum mounted coaxially within the said basket, the said drum being capable of rotatin at a speed different. from that of the basket and being provided with annular projections or webs formed with gaps, which webs extend up to a point adjacent the filtering wall and are effective in restraining the flow of the material, as the latter moves along the filtering wall. Impervious zones may be provided in the filtering wall opposite the rims of the annular Webs, which latter may be connected to each other by auxiliary webs.

The main object of the present invention is to improve the operation of the device and to ensure a rational extraction of the material treated. More particularly, the present invention makes it possible to overcome the lack of balance in the revolving assembly; to eliminate deposits from the material upon the rotating parts, through the injection of steam or the like; and, moreover, to avoid any detrimental moistening of the final product.

The special features and numerous advantages of the present invention will be apparent from the following statement wherein a few embodiments of the extractor according to the present invention are described with reference to the accompanying diagrammatical drawing in which:

Fig. 1 is an elevation, partly in section, of a centrifugal hydro-extractor;

Fig. 2 is a plan view, partly in section, of the extractor;

Fig. 3 is an elevation, partly in section, of a modified extractor;

Figs. 4 and 5 are fragmentary views in axial section and in elevation respectively, of another modification.

The extractor includes a basket 2 associated with a filtering or pervious wall 3 and mounted on a rotary shaft 5 by means of a flange 5, the whole assembly being enclosed in a housing I. On a shaft 4 there is mounted a drum 1 bearing outer annular webs 8, 9, Ii! provided with circumferentially staggered gaps H, l2, [3 allowing the passage of the material to be treated, which has a tendency to slip along the wall 3, but is retained for a suitable time by the webs 3, 9, iii. The material to be treated is supplied through the tube l5 to the distributor M which may consist of an annular apron memoer rigid with the drum. Advantageously, impervious strips 39, 40, M- are inserted into the wall 3, opposite the webs 8, 9, Ill.

The shafts 4 and 6 may be rotated at different speeds through any suitable means (not shown).

The extracted material is discharged through the collector it, while the liquid fiows off through the duct il. 7

When certain substances, for example, saline solutions, such as solutions of ammonium sul-' phate, sodium nitrate, etc., are under treatment, the filtering wall, which is generally formed of wire fabric, may get rapidly clogged on account of solid particles that become deposited, more specially by reason of the precipitation of the salts on the wires of the, metal fabric due to the cooling down of the mother-liquors.

According to this invention, such clogging may be avoided by washing the filtering wall, preferably in a continuous way, by means of jets, directed against the said filtering wall, of a medium, for instance steam or'water, capable of removing, for example by way of. dissolution, the particles deposited thereon, the said jets being delivered from injector devices revolving with the drum and lodged in the various annular compartments determined by. the annular webs 8, 9, Ill.

The steam or water injector devices comprise for example tubes 29, 3i), 3! provided with bore holes or slots and supplied with washing medium through pipes 32, 33, 38, connected, via bore holes in the shaft 4, with a longitudinal bore 35 formed in the said shaft and communicating with a source of steam or water.

The steam or water injector devices may be located adjacent the trailing edges (it is to say the edges which are second to pass opposite a given point of the basket on account of the relative movement of the drum and the basket) of the gaps across which the material being treated flows out of the annular compartments. Consequently, the stream of injected medium is directed against a momentarily uncovered portion of the wall 3, which makes possible an efficient washing of the said wall without at the same time wetting the material. Webs 36, 31, 38 and23, 24, 25 may be provided on one or on either side of the tubes 29, 3i), 3!, in order to better isolate the said tubes, the webs 23, 24, 23 serving moreover to detach the particles that may adhere accidentally to the inner face of the wallv 3, and may constitute an unbalanced weight. Alternately, the tubes, 29, 39, 3! may-be incorporated each in one of the webs interposed between the annular members 8, 9, l0.

However, in the treatment of certain materials, such as sugar, it is desirable to wet the material in the course of treatment, in order to keep it at a suitable degree of fluidity. To this end, and according to my invention, washing medium, for example, steam or water, may be injected in one or more points by means of devices arranged to revolve with the drum and which, therefore, move slowly with respect to the basket and perform their washing action for a suflicient period of time. If desired, such washing may be combined'with the injection effected via the tubes 29, 30, 3|, for example by connecting to the latter further perforated or 7 4| respectively, so as to present a pluralityof stepped cones. This is effective in an increase in the capacity of the successive compartments. Owing to this arrangement, the axial length of the said compartments, and consequently of the basket, may be shortened, without reducing the capacity of the extractor. The resulting reduction in the axial length of the non-supported portion of the movable assembly is a highly desirable feature.

It has further been found that the cooling down of the material as it enters the distributor I4 may cause the formation of crusts, which.

would finally clog the outlets from the distributor with the result that the extracting process will be arrested.

To avoid thisdrawback, steam or the like may be injected into the distributor l4 via a fixed pipe 43, the jet of steam sweeping the whole of the inner surface of the rotary distributor. With the same object in view and, if desired, in addition to the pipe 43, a shell or jacket supplied with steam or the like may be provided around thedistributor l4. Such jacket may be formed, for example, by a'chamber45interposed. in the flow of the pipes such as 33, 34 (Figs. 4 and 5).

The distributor 14 may be constituted by a simple annular apron member. However, as shown in Figs. 4 and 5, the distributor may be made for example in the shape of a frusto -conical basin formed with two arcuate hollow, arms 46, 41 extending therefrom and discharging at with the discharge openings of the extractor, while their other ends project into an annular opening 28 of the collector Hi.

In order to prevent wet vapours that may escape past the nozzles 21, especially when large quantities of steam are injected, from entering the collector l6, provision is made at the free end of each nozzle 21, of a blade 44, the concave face of the blades looking in the direction of the rotation of the revolving assembly. Owing to the action of these blades, the air contained in the collector l6 enters with force into the nozzles 21, thus preventing any escape of steam therefrom, without interfering with the discharge of the product.

WhatIclaim is:

1. In a centrifugal extractor, the combination with a conical basket having a screen, of a conical drum within and axially alined with said basket and having circumferential webs projecting in direction towards the basket, means for r0- tating the drum and basket at relatively different speeds, the annular webs on the drum being provided with gaps which are circumferentially-oflset from each other, circumferential ribs on the screen of the basket projecting in direction towards the webs and in close opposition thereto whereby annular compartment are provided between said webs, ribs, drum and basket respectively, means for supplying the material to be treated between the drum and the basket, and means for directing jets of liquid against the gaps only of the drum, whereby the material in the annular compartments is flowed through said two diametrally opposed points, 48, 49 at the end of smallest diameter of thebasket 2. I

It will be apparentthatthe various injections of steam or other washing media promote the production of'wet vapours in the space between the drum and the basket. Under the eiTect of the centrifugal force, such vapours travel towards the discharge end of the extractor and may moisten the final product. V

In order to prevent liquid or even steam from being discharged together with the final product, the collector I6 is spaceda certain distance apart from the housing I, and the material whichhas undergone the liquid-extraction process is discharged via nozzles 21'having one end connected 7 gaps.

2. In a centrifugal extractor, the combination with a conical basket having a screen thereon, of a conical drum within and in axial alinement with said screen, annular webs projecting from the drum in direction towards the screen of the basket, said webs being provided with gaps circumferentially staggered on the drum, annular ribs on the screen of the basket projecting in direction toward the webs and in close opposition thereto, means for supplying the material to be treated between the drum and. the basket, meansfor rotating the drum and basket at relatively different speeds, and means adjacent the trailing edge of each gap for supplying a stream of fluid into the space between the webs and ribs, whereby the material accumulated in each an- 'nular space formed by said webs and rib is 'sloughed through the gap into the next adjacent annular compartment between drum and basket. 3. In an extractor of the character described, thev combination of a conical basket having a screen, a drum within and in axial alinement therewith, a plurality of annular webs projecting from the drum in direction towards the basket, said webs being provided with gaps circumferentially oifset from each other, a plurality of ribs on the screen of the basket in opposition to said webs and projecting towards the same, whereby into the next adjacent annular compartment of the drum.

4. A centrifugal extractor, including in combination a conical basket provided with a screen, a conical drum within and in axial alinement with said basket, a plurality of circumferential webs projecting from the surface of the drum in direction towards the basket, said annular Webs being provided with gaps circumferentially staggered thereon, a plurality of annular ribs on the screen surface projecting in direction towards the drum and in close opposition to the free ends of the webs of the drum, whereby a plurality of annular compartments are provided, each compartment being adapted to communication with the next adjacent compartment through one of the gaps, means for rotating the basket and drum at relatively different speeds, means for supplying the material to be treated to the space between the drum and the screen, and means r0- tating with the drum and confined on the drum to zones adjacent the gaps l" or supplying washing fluid to the annular compartments for sloughing the material in said compartments directly through said gaps.

5. An extractor of the character described, comprising in combination with a conical basket having a screen, a conical drum within and in axial alinement with said basket, a plurality of annular Webs projecting from the surface of the drum in direction towards said screen, said webs having gaps which are circumferentially staggered relatively to each other, a plurality of annular ribs on the surface of the screen in opposition to and projecting closely to the free ends of the webs of the drum, whereby a plurality of annular compartments are formed communicating with each other through the staggered gaps, means for rotating said basket and drum at relatively different speeds, means for supplying the material to be treated between the drum and basket, and means extending in each compartment across the gap and across the compartment adjacent the gap for supplying washing fluid to the compartment for sloughing off the material in said compartment through the gap to the next adjacent compartment without affecting the material in said annular compartment remote from said gap.

6. In an extractor of the character described, the combination of a conical basket having a screen thereon, a conical drum within and in axial alinement with said basket, a plurality of annular webs on the surface of the drum projecting in direction towards the basket, said webs being provided with gaps which are circumferentially offset relatively to each other, a plurality of ribs projecting from the screen in direction towards the drum in close opposition to the ends of the annular webs, whereby a plurality of annular compartments are formed between drum and basket, said webs and ribs respectively, means for supplying material to the space be tween said drum and basket, means for rotating said drum and basket at relatively different speeds, and meansin the form of pipes rotating with the drum and extending in the compartments across the gaps thereof and adjacent the trailing edge of the gaps for supplying washing fluid to the material in said compartment for sloughing it through the gap to the next adjacent compartment.

7. In a centrifugal extractor of the character described, the combination of a conical basket having a screen thereon, the screen being assembled of a plurality of alined circular conical portions, the smaller diameter of each conical portion being greater than the greater diameter of the next adjacent conicalportion in direction towards the apex, circumferential shoulders between each two adjacent conical portions, a conical drum Within and in axial alinement with the basket, means for rotating said drum and basket at relatively different spaces, means for supplying the material to be treated between said drum and basket, a plurality of webs projecting from the surface of the drum in direction towards the basket and in opposition to the circumferential shoulders thereof, and means for supplying washing fluid to said compartments for sloughing the material from the compartments.

8. In an extractor of the character described, the combination of a conical basket having a screen provided with circumferential shoulders between adjacent conical screen portions of different diameters, a drum within and in axial alinement with said screen, means for imparting relatively different speeds to said drum and basket, a plurality of webs projecting from said drum in direction towards the basket, said webs being provided with gaps circumferentially staggered thereon, means for supplying material to the space between the drum and the basket, and annular ribs at the shoulder portions of the screen projecting in opposition to the free ends of the webs and close to said webs, whereby a plurality of annular compartments are formed between said drum and screen sections and said webs and ribs, and means for supplying said annular compartments with washing fluid adjacent said gaps only on the drum.

ARMAND BAILLY. 

